docs: def handle_one_of(schema, field, validator, parent_schema):
      """Adds the validation logic for ``marshmallow.validate.OneOf`` by setting
      the JSONSchema `enum` property to the allowed choices in the validator.
  
      Args:
          schema (dict): The original JSON schema we generated. This is what we
              want to post-process.
          field (fields.Field): The field that generated the original schema and
              who this post-processor belongs to.
          validator (marshmallow.validate.OneOf): The validator attached to the
              passed in field.
          parent_schema (marshmallow.Schema): The Schema instance that the field
              belongs to.
  
      Returns:
          dict: A, possibly, new JSON Schema that has been post processed and
              altered.
      """
      if validator.choices:
          schema['enum'] = list(validator.choices)
          schema['enumNames'] = list(validator.labels)
  
      return schema